Response of cyanobacteria and macrophytes communities on selected nutrients in Slim River lake ecosystem

<p>This study aimed to determine the response of cyanobacteria and macrophytes</p><p>communities on selected nutrients in Slim River Lake ecosystem. The sampling was</p><p>carried out twice a month at six sampling sites for 13 mon...

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Bibliographic Details
Main Author: Amy Rose Aeriyanie A Rahman
Format: thesis
Language:eng
Published: 2021
Subjects:
Online Access:https://ir.upsi.edu.my/detailsg.php?det=7404
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Summary:<p>This study aimed to determine the response of cyanobacteria and macrophytes</p><p>communities on selected nutrients in Slim River Lake ecosystem. The sampling was</p><p>carried out twice a month at six sampling sites for 13 months for lake water and 12</p><p>months for stormwater runoff. Lake water level was measured monthly to develop a</p><p>bathymetric map. Total phosphorus and total nitrogen concentration in lake water and</p><p>stormwater runoff were analyzed using ascorbic acid and hydrazine reduction methods,</p><p>respectively. Internal nutrients loading was calculated during five identified dry</p><p>periods, while external nutrients loading was calculated at every storm event. Total</p><p>chlorophyll-a of all phytoplankton taxa, cyanobacteria biomass, cyanobacteria</p><p>biovolume, and total macrophyte abundance were also measured throughout the</p><p>sampling period. The result indicated that Slim River Lake has a mean depth of 3.84 m.</p><p>In-lake total phosphorus and total nitrogen concentrations were found to be</p><p>significantly correlated with internal total phosphorus (r=0.82, p<0.05) and total</p><p>nitrogen (r=0.60, p<0.05) loading. Meanwhile, total chlorophyll-a, cyanobacteria</p><p>biomass, and total cyanobacteria biovolume significantly correlated with internal total</p><p>phosphorus loading. In contrast, total macrophyte abundance significantly correlated</p><p>with external total phosphorus (r=0.50, p<0.05) and external total nitrogen (r=0.44,</p><p>p<0.05) loading. Based on PCA model, internal nutrients loading is a primary</p><p>contributor to the lake's eutrophication progression. In conclusion, sediments nutrient</p><p>is a significant source of nutrient which mainly enhance the primary productivity in</p><p>Slim River Lake. This research implicates that internal nutrients loading should be</p><p>reduced to manage eutrophication problem in this lake.</p>